SATEC PM180 Operation Manual - Manual (Page 18)

‎Chapter 2 Device Description Device Outputs
16 PM180 Substation Automation Unit
unlimited number of post-event cycles. The length of the captured waveforms is only
restricted by the size of the allocated logging memory.
VDC Input
One high-impedance DC voltage input (300VDC range) V4, is normally intended for
monitoring the substation battery. It is sampled at a rate of 2 samples per cycle (each
8 or 10 ms) and synchronized to the AC sampling circuitry.
The waveform recorder can provide recording of VDC data simultaneously with the
AC input channels that allows testing the behavior of the substation battery under
load at the time of a fault.
The VDC drop can also trigger a setpoint to provide an external alarm indication
through a relay output or communications.
Digital Inputs
The PM180 can monitor up to 3 removable 16-channel digital input modules with a
total of 48 inputs. The modules may be ordered with input options for dry contacts, or
24V, 125V and 250V wet inputs.
All digital inputs are sampled at a rate of 16 samples per cycle and synchronized to
the AC sampling circuitry. This gives time stamping of the input transitions with a
1-ms resolution at 60 Hz, or 1.25-ms at 50 Hz.
Digital inputs have a programmable debounce time from one to 100 milliseconds in
groups of eight inputs. Each input can be independently linked to any device counter,
Energy/TOU system register, setpoint, Fault recorder, and Sequence-of-Events
recorder.
The device waveform recorder provides synchronous recording of the 48 digital input
channels together with the AC waveforms making it easy to correlate the operation of
the station protection relays at the time of a fault.
Analog Inputs
The PM180 monitors up to 16 analog input (AI) channels, which may be used for
measuring DC and low frequency currents and volts.
The following plug-in AI modules may be ordered with the device:

4-channel optically isolated 4 AI/AO modules with optional
ranges of 0-1 mA, ±1 mA, 0-20 mA, or 4-20 mA, 0-50 mA or
±10 V. The 0-1 mA and ±1 mA analog inputs can measure
100% overload currents up to 2 mA and ±2 mA.
The PM180 may be equipped with three 4-channel AI/AO modules.
The scan time for regular analog inputs is 2 cycles (32 ms at @ 60Hz and 40 ms @
50Hz). AI readings and triggers are updated each 1/2-cycle.
Each analog input can be independently scaled to provide true readings in the user-
defined engineering units (see
Programming Analog Inputs in Chapter 7).
NOTES:
1. If you use both 4-channel and 8-channel AI
modules in the same device, put the
4-channel AI modules in slots with lower
numbers, i.e., into the left side slots.
2. If you use regular 4-channel modules and
fast 8-channel AI modules, the regular
inputs are scanned at a usual rate.
Device Outputs
Analog Outputs
The PM180 supports up to four removable 4-channel 4AI/4AO modules with a total of
16 analog output channels that can output DC currents proportional to the measured
analog quantities. All outputs are optically isolated and have an internal power